Bicycle wheels are most often formed from a circular rim attached to a hub by a plurality of wire spokes arranged in a regular pattern. Generally, the spokes are arranged in an intersecting pattern wherein each spoke is about tangential to a circle concentric with the axis of rotation of the wheel. The spokes are passed or "threaded" through holes in hub flanges which lie in a plane generally perpendicular to the axis of rotation. The spokes are retained in the holes by an enlarged head portion. The enlarged head portion is larger than the diameter of the holes. Near the head portion the spoke is bent at right angles so that the spoke may be directed toward the rim. Each spoke has a screw-threaded end which extends through a hole in the rim and is secured therein by a nipple which is screwed onto the threaded end.
Building such spoked wheels is a complicated, time-taking process which requires considerable skill. A builder must be conscious always of the required intersection pattern of the spokes. No matter how much skill is acquired by a wheel builder, threading spokes through holes in hub flanges and locating the correct hole in a rim in which to insert a particular spoke still consumes time. Thus, in the total cost of building a wheel, the cost of labor may be a significant factor.
Machines have been devised to build spoked wheels with minimum involvement of skilled personnel. These machines, however, have been devised to mimic the actions of a human in building the wheel. The machine must perform the complicated function of threading a spoke through a hole in a hub flange, turning the spoke to correctly seat the spoke head in the hole, and directing the threaded end of the spoke, at the correct angle, into the correct hole in the rim. Such wheel building machines are extremely complicated, and thus may be subject to frequent breakdown. The complicated motions and operations required are such that it still takes the best of such machines about fifteen minutes to build a wheel. A skilled wheel builder may build a similar wheel in about one hour. This being the case, building wheels using cheap labor is still a viable option to building wheels by machine.